Coming, bat-inspired flying robots

Forget Batman as real life bats have inspired researchers to develop small flying vehicles with flapping wings.

By exploring how creatures in nature are able to fly by flapping their wings, Virginia Tech researchers hope to apply that knowledge toward 'micro air vehicles'.

"Bats are very agile and can change their flight path very quickly - showing high maneuverability for mid-flight prey capture, so it's of interest to know how they do this," explained Danesh Tafti, professor in department of mechanical engineering at Virginia Tech.

In the study of fruit bat wings, the researchers used experimental measurements of the movements of the bats' wings in real flight.

They then used analysis software to see the direct relationship between wing motion and airflow around the bat wing.

The researchers found how bat wings manipulated the wing motion with correct timing to maximise the forces generated by the wing.

For example, it increases the area of the wing by about 30 percent to maximise favourable forces during the downward movement of the wing.

It decreases the area by a similar amount on the way up to minimise unfavourable forces.

The force coefficients generated by the wing are "about two to three times greater than a static airfoil wing used for large airplanes", explained Kamal Viswanath, research engineer at the US Naval Research Lab's laboratories for computational physics and fluid dynamics.

The researchers are now exploring to deconstruct the seemingly complex motion of the bat wing into simpler motions, which is necessary to make a bat-inspired flying robot, said the report published in the journal Physics of Fluids.